The invention relates to universal joints of a kind comprising an outer element, substantially in the form of a bowl and, having a cylindrical bore in which tracks are formed, an inner element housed in this bore and presenting a convex external grooved surface and connecting members, particularly balls, disposed respectively in a track of the outer element and in a groove of the inner element. These connecting members are held in position by a cage which has a concave internal surface adapted to cooperate with a convex external surface of the inner element and a convex external surface. Removable positioning means are also provided to stop the cage with respect to the outer element.
Such universal joints are used especially for the homokinetic transmission of rotational movements in motor vehicles.
Depending on the situation, the transmission of the rotational movement may be accompanied by the inner element sliding with respect to the outer element (sliding universal joints), or may take place without any axial sliding movement of the inner element with respect to the outer element (fixed universal joints).
Removable means have already been proposed for positioning the cage so as to transform a sliding universal joint into a fixed universal joint and conversely.
However, the solutions proposed up to now are relatively complicated and involve difficulties in handling and mounting.